Тимошин Е.С., Тимошин С.И. Извлечение поляризационных

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¨¸Ó³ ¢ —Ÿ. 2014. ’. 11, º 2(186). ‘. 153Ä161
”ˆ‡ˆŠ ‹…Œ…’›• —‘’ˆ– ˆ ’Œƒ Ÿ„. ’…ˆŸ
ˆ‡‚‹…—…ˆ… ‹Ÿˆ‡–ˆ›•
‘’“Š’“›• ”“Š–ˆ‰ ˆ‡ ‘ˆŒŒ…’ˆ‰
‚ ƒ‹“Š…““ƒŒ ‘‘…Ÿˆˆ
‘ “—‘’ˆ…Œ …‰’ˆ
…. ‘. ’¨³μϨ´, ‘. ˆ. ’¨³μϨ´
ƒμ³¥²Ó¸±¨° £μ¸Ê¤ ·¸É¢¥´´Ò° ɥ̴¨Î¥¸±¨° Ê´¨¢¥·¸¨É¥É ¨³. . . ‘ÊÌμ£μ, ƒμ³¥²Ó, ¥²μ·Ê¸¸¨Ö
·¥¤²μ¦¥´ ´μ¢Ò° ¶μ¤Ìμ¤ ± ¨§¢²¥Î¥´¨Õ ¶μ²Ö·¨§ Í¨μ´´ÒÌ ¸É·Ê±ÉÊ·´ÒÌ ËÊ´±Í¨° ´Ê±²μ´ ¨§
¨§³¥·Ö¥³ÒÌ ¸¨³³¥É·¨° ¢ £²Ê¡μ±μ´¥Ê¶·Ê£μ³ ²¥¶Éμ´-´Ê²μ´´μ³ · ¸¸¥Ö´¨¨ ¸ § ·Ö¦¥´´Ò³ ¸² ¡Ò³
Éμ±μ³, ¶·¨³¥´¨³Ò° ¤²Ö ²Õ¡μ° ³¨Ï¥´¨.
A new approach to the extraction of the polarized structure function of the nucleon from the
measurable asymmetries in the deep inelastic leptonÄnucleon scattering with the charged weak current
applicable for any target is proposed.
PACS: 13.88.+c; 13.15.+g; 13.40.Ks; 13.60.Hb; 14.20.Dh
‚‚…„…ˆ…
‚ Š•„ ¸¶¨´ ´Ê±²μ´ ¶·¥¤¸É ¢²Ö¥É¸Ö Î¥·¥§ ¢±² ¤Ò ¸μ¸É ¢²ÖÕÐ¨Ì ¥£μ ±¢ ·±μ¢ ¨ £²Õμ´μ¢ ¸²¥¤ÊÕШ³ μ¡· §μ³:
1
1
= ΔΣ + Δg + Lq + Lg ,
2
2
£¤¥ ΔΣ, Δg Å ¢±² ¤Ò μÉ ¸¶¨´μ¢ ±¢ ·±μ¢ ¨ £²Õμ´μ¢ ¸μμÉ¢¥É¸É¢¥´´μ; Lq , Lg Å μ·¡¨É ²Ó´Ò¥ Ê£²μ¢Ò¥ ³μ³¥´ÉÒ ±¢ ·±μ¢ ¨ £²Õμ´μ¢.
‚ ´ ¸ÉμÖÐ¥¥ ¢·¥³Ö ´ ¤¥¦´μ Ê¸É ´μ¢²¥´μ, ÎÉμ μ¤´Ê É·¥ÉÓ ´Ê±²μ´´μ£μ ¸¶¨´ ´¥¸ÊÉ
±¢ ·±¨ ¨ ´É¨±¢ ·±¨ [1Ä3]. ¤¨´ ¨§ ´ ¨¡μ²¥¥ ¢ ¦´ÒÌ μɱ·ÒÉÒÌ ¢μ¶·μ¸μ¢ Å ¨¸Éμ䨱 μ¸É ¢Ï¥°¸Ö 2/3 ¸¶¨´ ´Ê±²μ´ . μ ¤ ´´Ò³ ¢¸¥Ì ¸μ¢·¥³¥´´ÒÌ Ô±¸¶¥·¨³¥´Éμ¢ (SMC,
COMPASS, HERMES, RHIC), ¶μ²Ö·¨§ ꬅ £²Õμ´μ¢ ´¥ ³μ¦¥É ¡ÒÉÓ ¡μ²ÓÏμ° ¨ ¸μ¸É ¢²Ö¥É
|Δg| 0,3. ’ ± Ö ¢¥²¨Î¨´ Δg ´¥ μ¡ÑÖ¸´Ö¥É · §´¨ÍÊ ³¥¦¤Ê Ô±¸¶¥·¨³¥´É ²Ó´Ò³ §´ Î¥´¨¥³ ±¸¨ ²Ó´μ£μ § ·Ö¤ ´Ê±²μ´ a0 (HERMES ∼ 0,33, COMPASS ∼ 0,35) ¨ ¶·¥¤¸± § ´¨¥³ ±¢ ·±-¶ ·Éμ´´μ° ³μ¤¥²¨ ΔΣ ∼ 0,6 Î¥·¥§ ±¸¨ ²Ó´ÊÕ ´μ³ ²¨Õ (¢ ±¢ ·±-¶ ·Éμ´´μ°
³μ¤¥²¨ a0 = ΔΣ). ‚ Éμ ¦¥ ¢·¥³Ö £²Õμ´´ Ö ¶μ²Ö·¨§ ꬅ Δg ∼ 0,2−0,3 ¢¸¥ ¥Ð¥ ¤¥² ¥É
¸ÊÐ¥¸É¢¥´´Ò³ ¥¥ ¢±² ¤ ¢ ¸¶¨´ ´Ê±²μ´ [3].
154 ’¨³μϨ´ …. ‘., ’¨³μϨ´ ‘. ˆ.
‚±² ¤Ò μÉ Ê£²μ¢ÒÌ μ·¡¨É ²Ó´ÒÌ ³μ³¥´Éμ¢ ±¢ ·±μ¢ ¨ £²Õμ´μ¢ É ±¦¥ Ö¢²ÖÕÉ¸Ö ¢ ¦´μ° ¸μ¸É ¢²ÖÕÐ¥° ¢ ¶μ²´μ³ ¸¶¨´μ¢μ³ ¡ ² ´¸¥ ´Ê±²μ´ . „μ¸Éʶ ± ´¨³ ¢μ§³μ¦¥´ Î¥·¥§
¨§³¥·¥´¨Ö μ¡μ¡Ð¥´´ÒÌ ¶ ·Éμ´´ÒÌ · ¸¶·¥¤¥²¥´¨° ¢ Ô±¸±²Õ§¨¢´ÒÌ ¶·μÍ¥¸¸ Ì £²Ê¡μ±μ
¢¨·ÉÊ ²Ó´μ£μ ±μ³¶Éμ´μ¢¸±μ£μ · ¸¸¥Ö´¨Ö ¨ Ô²¥±É·μ·μ¦¤¥´¨Ö ¢¥±Éμ·´ÒÌ ³¥§μ´μ¢ [3].
μ¢ Ö ¨´Ëμ·³ Í¨Ö μ ¢±² ¤ Ì μɤ¥²Ó´ÒÌ ·μ³ Éμ¢ ±¢ ·±μ¢ ¨ ´É¨±¢ ·±μ¢, ¢ ²¥´É´ÒÌ
±¢ ·±μ¢, ¶μ²´μ³ ±¢ ·±μ¢μ³ ¢±² ¤¥ ¢ ´Ê±²μ´´Ò° ¸¶¨´ ³μ¦¥É ¡ÒÉÓ ¶μ²ÊÎ¥´ ¢ Ô±¸¶¥·¨³¥´É Ì ¶μ £²Ê¡μ±μ´¥Ê¶·Ê£μ³Ê · ¸¸¥Ö´¨Õ ¸ § ·Ö¦¥´´Ò³ Éμ±μ³ ´ ¶μ²Ö·¨§μ¢ ´´ÒÌ ³¨Ï¥´ÖÌ.
Š É ±¨³ ¶·μÍ¥¸¸ ³ μÉ´μ¸¨É¸Ö £²Ê¡μ±μ´¥Ê¶·Ê£μ¥ · ¸¸¥Ö´¨¥ ´¥°É·¨´μ ¨ § ·Ö¦¥´´ÒÌ
²¥¶Éμ´μ¢ (l = e, μ) ´ ´Ê±²μ´ Ì ¸ μ¡³¥´μ³ W -¡μ§μ´μ³. ·¥¨³ÊÐ¥¸É¢μ ¨Ì ¶μ ¸· ¢´¥´¨Õ
¸ ¶·μÍ¥¸¸ ³¨ ¸ Ô²¥±É·μ³ £´¨É´Ò³ Éμ±μ³ ¸μ¸Éμ¨É ¢ Éμ³, ÎÉμ ¨³¥ÕÉ¸Ö ¤¢¥ ´¥§ ¢¨¸¨³Ò¥
¶μ²Ö·¨§ Í¨μ´´Ò¥ ¸É·Ê±ÉÊ·´Ò¥ ËÊ´±Í¨¨ g1 ¨ g5 ¤²Ö ¶·μ¤μ²Ó´μ° ¶μ²Ö·¨§ ͨ¨ ³¨Ï¥´¨ [4].
‘ɷʱÉÊ·´Ò¥ ËÊ´±Í¨¨ g1 ¨ g5 ¸μμÉ¢¥É¸É¢ÊÕÉ ²¨´¥°´Ò³ ±μ³¡¨´ ֳͨ ¢±² ¤μ¢ ±¢ ·±μ¢ÒÌ
¸¶¨´μ¢: ¸μÌ· ´ÖÕÐ Ö Î¥É´μ¸ÉÓ ¸É·Ê±ÉÊ·´ Ö ËÊ´±Í¨Ö g1 Ö¢²Ö¥É¸Ö ¸Ê³³μ° ¢±² ¤μ¢ ±¢ ·±μ¢
¨ ´É¨±¢ ·±μ¢ (Δq + Δq), ´ ·ÊÏ ÕÐ Ö Î¥É´μ¸ÉÓ ¸É·Ê±ÉÊ·´ Ö ËÊ´±Í¨Ö g5 Å · §´μ¸ÉÓÕ
±¢ ·±μ¢ÒÌ ¨ ´É¨±¢ ·±μ¢ÒÌ ¢±² ¤μ¢ (Δq − Δq).
²¨Î¨¥ ¤¢ÊÌ ¨§³¥·Ö¥³ÒÌ ¸É·Ê±ÉÊ·´ÒÌ ËÊ´±Í¨° g1 ¨ g5 ¸ · §²¨Î´μ° ±μ³¡¨´ ͨ¥° Δq ¨ Δq ¶μ§¢μ²Ö¥É ¶μ²ÊΨÉÓ μɤ¥²Ó´μ ¢±² ¤Ò ¢ ²¥´É´ÒÌ ¨ ³μ·¸±¨Ì ±¢ ·±μ¢, É. ¥.
¤ ¥É ¤μ¸Éʶ ± ·μ³ Éμ¢μ° ¸É·Ê±ÉÊ·¥ ³¨Ï¥´¨ [4]. ɳ¥É¨³, ÎÉμ ¢ ¨´±²Õ§¨¢´μ³ ²¥¶Éμ´´Ê±²μ´´μ³ £²Ê¡μ±μ´¥Ê¶·Ê£μ³ · ¸¸¥Ö´¨¨ ¸ γ-μ¡³¥´μ³ ¤μ¸Éʶ´ Éμ²Ó±μ ±μ³¡¨´ ꬅ Δq +
Δq. μÔÉμ³Ê ¢μ§³μ¦´μ¸ÉÓ · §¤¥²¥´¨Ö ¢±² ¤μ¢ ±¢ ·±μ¢ ¨ ´É¨±¢ ·±μ¢ μɤ¥²Ó´μ ¶μ ·μ³ É ³ Ö¢²Ö¥É¸Ö ¸ÊÐ¥¸É¢¥´´Ò³ ¶·¥¨³ÊÐ¥¸É¢μ³ £²Ê¡μ±μ´¥Ê¶·Ê£μ£μ · ¸¸¥Ö´¨Ö ¸ § ·Ö¦¥´´Ò³
¸² ¡Ò³ Éμ±μ³.
±¸¶¥·¨³¥´ÉÒ ¶μ £²Ê¡μ±μ´¥Ê¶·Ê£μ³Ê ²¥¶Éμ´-´Ê±²μ´´μ³Ê · ¸¸¥Ö´¨Õ ¸ § ·Ö¦¥´´Ò³
¸² ¡Ò³ Éμ±μ³ ³μ£ÊÉ ¡ÒÉÓ ·¥ ²¨§μ¢ ´Ò ´ Ô²¥±É·μ´-¶·μÉμ´´ÒÌ (ep) ±μ²² °¤¥· Ì, ´ ¶·¨³¥·, ¢ · ³± Ì ¶·μ¥±Éμ¢ LHeC, eRHIC ¨ EIC [5Ä10], ¶·¨ ¡μ²ÓÏ¨Ì Q2 .
’¥Ì´μ²μ£¨Ö ³Õμ´´ÒÌ ±μ²² °¤¥·μ¢ ¤ ¥É ¢μ§³μ¦´μ¸ÉÓ ¶μ²ÊÎ ÉÓ ¢Ò¸μ±μËμ±Ê¸¨·μ¢ ´´Ò¥ ¶Êα¨ ´¥°É·¨´μ ¨ ´É¨´¥°É·¨´μ μÉ · ¸¶ ¤μ¢ ³Õμ´μ¢ (´¥°É·¨´´Ò¥ Ë ¡·¨±¨) [4,11,12].
´¥°É·¨´´μ° Ë ¡·¨±¥ ³μ¦´μ ´ ¡· ÉÓ ´¥μ¡Ì줨³ÊÕ ¸É ɨ¸É¨±Ê ʦ¥ ¸ ¤μ¸É Éμδμ
³ ²Ò³¨ ³¨Ï¥´Ö³¨; ¸μ¢·¥³¥´´Ò¥ ɥ̴μ²μ£¨¨ ¶μ§¢μ²ÖÕÉ ¸μ§¤ ¢ ÉÓ ¶μ²Ö·¨§μ¢ ´´Ò¥ ³¨Ï¥´¨ ³ ¸¸μ° ¤μ 1 ±£, ±μÉμ·Ò¥ ¢¶μ²´¥ ¶μ¤Ìμ¤ÖÉ ¤²Ö ´¥°É·¨´´ÒÌ Ô±¸¶¥·¨³¥´Éμ¢.
±ÉÊ ²Ó´Ò³ Ö¢²Ö¥É¸Ö ¨¸¸²¥¤μ¢ ´¨¥ ¸¶¨´μ¢μ° ¸É·Ê±ÉÊ·Ò ´Ê±²μ´ ¢ ¶·μÍ¥¸¸ Ì £²Ê¡μ±μ´¥Ê¶·Ê£μ£μ · ¸¸¥Ö´¨Ö ¸ § ·Ö¦¥´´Ò³ Éμ±μ³, ¶μ¸±μ²Ó±Ê ¶μ¸É ´μ¢± Ô±¸¶¥·¨³¥´Éμ¢ ´ ¨Ì μ¸´μ¢¥, ± ± ¶μ± § ´μ ¢ÒÏ¥, ¸É ´μ¢¨É¸Ö ¢¶μ²´¥ ·¥ ²Ó´μ°.
´ ²¨§ ¸¶¨´μ¢μ° ¸É·Ê±ÉÊ·Ò ´Ê±²μ´ ¢ ´¥°É·¨´´ÒÌ ¶·μÍ¥¸¸ Ì £²Ê¡μ±μ´¥Ê¶·Ê£μ£μ · ¸¸¥Ö´¨Ö ¨³¥¥É¸Ö ¢ · ¡μÉ¥ [13], £¤¥ ¤²Ö ÔÉμ£μ ¨¸¶μ²Ó§ÊÕÉ¸Ö ¶¥·¢Ò¥ ³μ³¥´ÉÒ ¸É·Ê±ÉÊ·´μ° ËÊ´±Í¨¨ g1νN (x) ¨ ´ ·ÊÏ ÕÐ¥° Υɴμ¸ÉÓ ¸É·Ê±ÉÊ·´μ° ËÊ´±Í¨¨ AνN
1 (x). ¤´ ±μ
¢μ§³μ¦´μ¸É¨ ¨§¢²¥Î¥´¨Ö ¸ ³¨Ì ¸É·Ê±ÉÊ·´ÒÌ ËÊ´±Í¨° g1νN (x) ¨ AνN
(x)
¨§ ´ ¡²Õ¤ ¥1
³ÒÌ ¢¥²¨Î¨´ ´¨± ± ´¥ μ¡¸Ê¦¤ ÕɸÖ. ¸ ³μ³ ¤¥²¥ ÔÉμÉ ¢μ¶·μ¸ ´¥É·¨¢¨ ²Ó´Ò°, ¶μ¸±μ²Ó±Ê ¨³¥ÕÉ¸Ö ¤¢¥ ´¥§ ¢¨¸¨³Ò¥ ¶μ²Ö·¨§ Í¨μ´´Ò¥ ¸É·Ê±ÉÊ·´Ò¥ ËÊ´±Í¨¨ ¢ ´¥°É·¨´´ÒÌ ¶·μÍ¥¸¸ Ì, ´¥ μ¤´ ¸É·Ê±ÉÊ·´ Ö ËÊ´±Í¨Ö g1 , ± ± ¢ £²Ê¡μ±μ´¥Ê¶·Ê£μ³ · ¸¸¥Ö´¨¨
¸ Ô²¥±É·μ³ £´¨É´Ò³ Éμ±μ³ (¤²Ö ¶·μ¤μ²Ó´μ ¶μ²Ö·¨§μ¢ ´´μ° ³¨Ï¥´¨ ¢±² ¤μ³ ¸É·Ê±ÉÊ·´μ° ËÊ´±Í¨¨ g2 ¢ ¸¥Î¥´¨¥ ³μ¦´μ ¶·¥´¥¡·¥ÎÓ). ‚ · ¡μÉ Ì [14, 15] ±¢ ·±μ¢Ò¥ ¢±² ¤Ò
¢ ´Ê±²μ´´Ò° ¸¶¨´ ¢ £²Ê¡μ±μ´¥Ê¶·Ê£μ³ · ¸¸¥Ö´¨¨ ( ´É¨)´¥°É·¨´μ ´ ´Ê±²μ´ Ì ¶μ²ÊÎ¥´Ò É즥 ¸ ¶μ³μÐÓÕ ¶¥·¢ÒÌ ³μ³¥´Éμ¢ ¶μ²Ö·¨§ Í¨μ´´ÒÌ ¸É·Ê±ÉÊ·´ÒÌ ËÊ´±Í¨° g1
¨ g6 . ‘ ³¨ ¸É·Ê±ÉÊ·´Ò¥ ËÊ´±Í¨¨ g1 ¨ g6 ¶·¥¤² £ ¥É¸Ö ¨§¢²¥± ÉÓ ¨§ ¢¨·ÉÊ ²Ó´ÒÌ
¸¨³³¥É·¨° A1 ¨ A6 , ¶μ¸É·μ¥´´ÒÌ ¨§ ¶μ²´ÒÌ ¸¥Î¥´¨° ¶μ£²μÐ¥´¨Ö ¢¨·ÉÊ ²Ó´ÒÌ W -
ˆ§¢²¥Î¥´¨¥ ¶μ²Ö·¨§ Í¨μ´´ÒÌ ¸É·Ê±ÉÊ·´ÒÌ ËÊ´±Í¨° ¨§ ¸¨³³¥É·¨° 155
¨ Z-¡μ§μ´μ¢ ¶μ²Ö·¨§μ¢ ´´Ò³ ´Ê±²μ´μ³, Î¥·¥§ ±μÉμ·Ò¥ ¢Ò· ¦ ÕÉ¸Ö ¨§³¥·Ö¥³Ò¥ ¸¨³³¥É·¨¨ Aν , Aν̄ . ¤´ ±μ ¶·μÍ¥¤Ê· ¶μ²ÊÎ¥´¨Ö A1 ¨ A6 ¨§ ¨§³¥·Ö¥³ÒÌ ¸¨³³¥É·¨° §¤¥¸Ó
¨³¥¥É ³¥¸Éμ Éμ²Ó±μ ¤²Ö Î ¸É´μ£μ ¸²ÊÎ Ö · ¸¸¥Ö´¨Ö ´ ¤¥°É·μ´´μ° ³¨Ï¥´¨ ¨ ¸ ¶·¨¢²¥Î¥´¨¥³ ËμÉμ´-´Ê±²μ´´μ° ¸¨³³¥É·¨¨ Ad1 £²Ê¡μ±μ´¥Ê¶·Ê£μ£μ · ¸¸¥Ö´¨Ö ¸ Ô²¥±É·μ³ £´¨É´Ò³
Éμ±μ³.
–¥²Ó ´ ¸ÉμÖÐ¥° · ¡μÉÒ Å ¶μ²ÊÎ¥´¨¥ ¸¶μ¸μ¡ ¨§¢²¥Î¥´¨Ö ¶μ²Ö·¨§ Í¨μ´´ÒÌ ¸É·Ê±ÉÊ·´ÒÌ ËÊ´±Í¨° g1 ¨ g6 ´¥¶μ¸·¥¤¸É¢¥´´μ ¨§ ¨§³¥·Ö¥³ÒÌ ¸¨³³¥É·¨° ¢ £²Ê¡μ±μ´¥Ê¶·Ê£μ³
· ¸¸¥Ö´¨¨ ¸ § ·Ö¦¥´´Ò³ ¸² ¡Ò³ Éμ±μ³ (μ¡³¥´ W -¡μ§μ´μ³), ¶·¨³¥´¨³μ£μ ¤²Ö ²Õ¡μ°
³¨Ï¥´¨.
1. „ˆ””……–ˆ‹œ›… ‘…—…ˆŸ …‰’ˆ›• –…‘‘‚
‘ ‡Ÿ†…›Œ ’ŠŒ
¸¸³μÉ·¨³ £²Ê¡μ±μ´¥Ê¶·Ê£μ¥ · ¸¸¥Ö´¨¥ ´¥°É·¨´μ ¨ ´É¨´¥°É·¨´μ ´ ¶μ²Ö·¨§μ¢ ´´ÒÌ ´Ê±²μ´ Ì ¸ § ·Ö¦¥´´Ò³ ¸² ¡Ò³ Éμ±μ³
ν(ν̄) + N → l− (l+ ) + X
(l = e, μ)
(1)
¢ ¡μ·´μ¢¸±μ³ ¶·¨¡²¨¦¥´¨¨ (·¨¸.).
·μÍ¥¸¸ £²Ê¡μ±μ´¥Ê¶·Ê£μ£μ · ¸¸¥Ö´¨Ö ´¥°É·¨´μ ´ ´Ê±²μ´ Ì ¸ § ·Ö¦¥´´Ò³ Éμ±μ³ ¢ ¡μ·´μ¢¸±μ³
¶·¨¡²¨¦¥´¨¨
„¨ËË¥·¥´Í¨ ²Ó´Ò¥ ¸¥Î¥´¨Ö ¶·μÍ¥¸¸μ¢ (1) ¨³¥ÕÉ ¢¨¤
p
a
dσν,ν̄ = dσν,ν̄
+ dσν,ν̄
,
£¤¥
a
=
dσν,ν̄
3 G2 M
αβ
ν,ν̄ d k
αβ
(L
±
L
)W
,
5
αβ
(2π)2 p · k
k0
ν,ν̄
Wαβ
= −gαβ W1ν,ν̄ +
¨
p
=
dσν,ν̄
(2)
1
i
pα pβ W2ν,ν̄ −
eαβρσ pρ q ρ W3ν,ν̄
M2
2M 2
3 G2 M
ν,ν̄ d k
(Lαβ ± Lαβ
,
5 ) Gαβ
2
(2π) p · k
k0
(3)
(4)
156 ’¨³μϨ´ …. ‘., ’¨³μϨ´ ‘. ˆ.
Gν,ν̄
αβ = −
i
i
ν,ν̄
σ
σ
−
eαβρσ q σ M 2 sσ Gν,ν̄
eαβρσ pρ sσ Gν,ν̄
+
(p
·
qs
−
s
·
qp
)G
1
2
3 +
M
M
1
2
1
+ 2 (pα sβ + pβ sα )Gν,ν̄
pα pβ (s · q)Gν,ν̄
gαβ (s · q)Gν,ν̄
4 +
5 +
6 ,
2
M
M
M2
Lαβ (k, k ) = k α k β + k α k β − g αβ (kk ),
αβρσ
kp kσ ,
Lαβ
5 (k, k ) = −ie
£¤¥ G Å ±μ´¸É ´É ”¥·³¨; M Å ³ ¸¸ ´Ê±²μ´ ; q = k − k ; s Å ¢¥±Éμ· ¶μ²Ö·¨§ ͨ¨
´Ê±²μ´ .
ν,ν̄
2
(ν, q 2 ) ¨ Gν,ν̄
W1,2,3
1...6 (ν, q ) Šʸ·¥¤´¥´´Ò¥ ¶μ ¸¶¨´Ê ¨ ¶μ²Ö·¨§ Í¨μ´´Ò¥ ¸É·Ê±ÉÊ·´Ò¥
ËÊ´±Í¨¨ ´Ê±²μ´ ¸μμÉ¢¥É¸É¢¥´´μ,
ν = p · q/M.
‚ μ¶·¥¤¥²¥´¨¨
ν,ν̄
Wαβ
¨
Gν,ν̄
αβ
μ¶ÊÐ¥´Ò β¥´Ò, ¶·μ¶μ·Í¨μ´ ²Ó´Ò¥ q α ¨²¨ q β , É ± ± ±
¶·¨ ¸¢¥·É±¥ ¸ ²¥¶Éμ´´Ò³ É¥´§μ·μ³ [Lαβ (k, k ) ± Lαβ
5 (k, k )] μ´¨ ¤ ÕÉ Î²¥´Ò, ¶·μ¶μ·Í¨μ´ ²Ó´Ò¥ ³ ¸¸ ³ ²¥¶Éμ´μ¢, ±μÉμ·Ò³¨ ³μ¦´μ ¶·¥´¥¡·¥ÎÓ. ɳ¥É¨³, ÎÉμ ¢ ¸¶¥Í¨ ²Ó´μ°
²¨É¥· ÉÊ·¥ (¸³., ´ ¶·¨³¥·, [4]) ¢¸É·¥Î ¥É¸Ö ´¥¸±μ²Ó±μ ¨´μ¥ μ¶·¥¤¥²¥´¨¥ ¤·μ´´μ£μ É¥´§μ· , ±μÉμ·μ¥ ¸μ¤¥·¦¨É ´¥ Ï¥¸ÉÓ, ± ± ¢ (4), ¶ÖÉÓ ¶μ²Ö·¨§ Í¨μ´´ÒÌ ¸É·Ê±ÉÊ·´ÒÌ ËÊ´±³μ¦´μ ¸¢¥¸É¨
ͨ°. Éμ μ¡Ê¸²μ¢²¥´μ É¥³, ÎÉμ É¥´§μ·´ÊÕ ¸É·Ê±ÉÊ·Ê eαβρσ pρ sσ ¶·¨ Gν,ν̄
3
± eαβρσ q ρ (p · qsσ − s · qpσ ) ¶·¨ Gν,ν̄
¸
Éμδμ¸ÉÓÕ
¤μ
¸² £ ¥³ÒÌ,
¶·μ¶μ·Í¨μ´ ²Ó´ÒÌ
qα
2
β
¨ q , ±μÉμ·Ò³¨, ± ± ʦ¥ ¡Ò²μ ¸± § ´μ, ³μ¦´μ ¶·¥´¥¡·¥ÎÓ. μÔÉμ³Ê Ψ¸²μ ¶μ²Ö·¨§μ¢ ´´ÒÌ ¸É·Ê±ÉÊ·´ÒÌ ËÊ´±Í¨° ³μ¦´μ ´ μ¤´Ê Ê³¥´ÓϨÉÓ § ¸Î¥É Gν,ν̄
3 . ‚ Éμ ¦¥ ¢·¥³Ö
¸²¥¤Ê¥É ¶μ¤Î¥·±´ÊÉÓ, ÎÉμ ¸É·Ê±ÉÊ·´ Ö ËÊ´±Í¨Ö g6ν,ν̄ ¢ ´ ¸ÉμÖÐ¥° · ¡μÉ¥ ¨ ¸É·Ê±ÉÊ·´ Ö
ËÊ´±Í¨Ö g5 ¢ [4] ¸μμÉ¢¥É¸É¢ÊÕÉ μ¤´μ³Ê ¨ Éμ³Ê ¦¥ É¥´§μ·Ê gαβ (s · q).
‘¥Î¥´¨¥ ´ ´¥¶μ²Ö·¨§μ¢ ´´μ° ³¨Ï¥´¨ § ¶¨¸Ò¢ ¥É¸Ö É ± (¸³., ´ ¶·¨³¥·, [16]):
a
d2 σν,ν̄
y ν,ν̄
= σ0 xy 2 F1ν,ν̄ (x, Q2 ) + (1 − y)F2ν,ν̄ (x, Q2 ) ± xy 1 −
F3 (x, Q2 ) , (5)
dx dy
2
£¤¥
G2
ν,ν̄
ν,ν̄
M E; F1ν,ν̄ = M W1ν,ν̄ ; F2,3
σ0 =
= νW2,3
;
π
2
ν
Q
; y = ; Q2 = −q 2 ;
x=
2M ν
E
E Å Ô´¥·£¨Ö ´¥°É·¨´μ ¨²¨ ´É¨´¥°É·¨´μ.
k
„²Ö ¶·μ¤μ²Ó´μ° ¶μ²Ö·¨§ ͨ¨ ´Ê±²μ´ (s = 0, PN
¢ ² ¡μ· Éμ·´μ° ¸¨¸É¥³¥,
|k|
PN Å ¸É¥¶¥´Ó ¶μ²Ö·¨§ ͨ¨) ¸¥Î¥´¨¥ (4) ¶μ²ÊÎ¥´μ ¢ ¢¨¤¥
p
d2 σν,ν̄
M xy ν,ν̄
M x ν,ν̄
= PN σ0 xy 2 1 +
g6 (x, Q2 ) − 2 − 2y −
g4 (x, Q2 )−
dx dy
E
E
M xy ν,ν̄
M x 1−y−
g5 (x, Q2 )±
−2 1+
E
2E
M xy ν,ν̄
2M x2 y ν,ν̄
M xy ν,ν̄
2
2
2
g1 (x, Q ) −
g2 (x, Q ) +
g (x, Q ) .
± xy 2 − y −
E
E
E 3
ˆ§¢²¥Î¥´¨¥ ¶μ²Ö·¨§ Í¨μ´´ÒÌ ¸É·Ê±ÉÊ·´ÒÌ ËÊ´±Í¨° ¨§ ¸¨³³¥É·¨° 157
‡¤¥¸Ó ¢¢¥¤¥´Ò ¡¥§· §³¥·´Ò¥ ¸É·Ê±ÉÊ·´Ò¥ ËÊ´±Í¨¨ [17]
g1 = M 2 νG1 , g2 = M ν 2 G2 , g3 = νG3 ,
ν
ν
G4 , g5 = ν 2 G5 , g6 =
G6 .
g4 =
M
M
‚ £²Ê¡μ±μ´¥Ê¶·Ê£μ° μ¡² ¸É¨ ¢¥²¨Î¨´ M/E 1, ¶μÔÉμ³Ê ¢ ÔÉμ³ ¶·¨¡²¨¦¥´¨¨ ¨³¥¥³
p
d2 σν,ν̄
= PN σ0 xy 2 g6ν,ν̄ (x, Q2 ) − 2 1 − y ×
dx dy
ν,ν̄
ν,ν̄
ν,ν̄
2
2
2
× g4 (x, Q ) + g5 (x, Q ) ± xy 2 − y g1 (x, Q ) .
‚§ ¨³μ¤¥°¸É¢¨¥ ¢¨·ÉÊ ²Ó´μ£μ ¡μ§μ´ ¸ ±¢ ·±μ³ ¸μÌ· ´Ö¥É ¸¶¨· ²Ó´μ¸ÉÓ, ±μ£¤ ¢¸¥³¨
³ ¸¸ ³¨ ¶·¥´¥¡·¥£ ¥É¸Ö, É ± ÎÉμ ¤·μ´´Ò° É¥´§μ· Tαβ = Wαβ + Gαβ , ¥¸²¨ · ¸¸³ É·¨¢ ¥É¸Ö ²¨¤¨·ÊÕШ° ¶μ·Ö¤μ±, ¤μ²¦¥´ ¨¸Î¥§ ÉÓ ¶·¨ ʳ´μ¦¥´¨¨ ´ ¢¥±Éμ· ¶·μ¤μ²Ó´μ°
¶μ²Ö·¨§ ͨ¨ ¡μ§μ´ εα [4]. μ¸±μ²Ó±Ê εα ³μ¦´μ ¶·¥¤¸É ¢¨ÉÓ ± ± ²¨´¥°´ÊÕ ±μ³¡¨´ Í¨Õ p ¨ q, ÔÉμ ʸ²μ¢¨¥ ¶μ¤· §Ê³¥¢ ¥É q α q β Tαβ = 0. ’죤 ¨§ (3) ¨ (4) ¶μ²ÊÎ ¥³
q α q β Tαβ = ν (F2 − 2xF1 ) + 2(sq) (g4 + g5 + xg6 ) = 0.
μÔÉμ³Ê ¢ ²¨¤¨·ÊÕÐ¥³ ¶μ·Ö¤±¥
g4 (x, Q2 ) + g5 (x, Q2 ) = −xg6 (x, Q2 ).
‘ ÊÎ¥Éμ³ ÔÉμ£μ ¸μμÉ´μÏ¥´¨Ö ¶μ²Ö·¨§ Í¨μ´´ Ö Î ¸ÉÓ ¸¥Î¥´¨° ¶·μÍ¥¸¸μ¢ (1) ¨³¥¥É ¢¨¤
p
d2 σν,ν̄
= PN xσ0 y1+ g6ν,ν̄ (x, Q2 ) ± y1− g1ν,ν̄ (x, Q2 ) ,
dx dy
(6)
£¤¥
y1 = 1 − y,
y1± = 1 ± y12 .
‘¥Î¥´¨Ö ¶·μÍ¥¸¸μ¢ (1) £²Ê¡μ±μ´¥Ê¶·Ê£μ£μ · ¸¸¥Ö´¨Ö ( ´É¨)´¥°É·¨´μ ´ ¶·μ¤μ²Ó´μ ¶μ²Ö·¨§μ¢ ´´μ° ³¨Ï¥´¨ ¢ ¸μμÉ¢¥É¸É¢¨¨ ¸ (2), (5), (6) ³μ¦´μ § ¶¨¸ ÉÓ ¸²¥¤ÊÕШ³ μ¡· §μ³:
d2 σν,ν̄
y ν,ν̄
= σ0 xy 2 F1ν,ν̄ (x, Q2 ) + y1 F2ν,ν̄ (x, Q2 ) ± xy 1 −
F (x, Q2 )+
dx dy
2 3
+ PN x y1+ g6ν,ν̄ (x, Q2 ) ± y1− g1ν,ν̄ (x, Q2 ) . (7)
ˆ§ (7) ¢¨¤´μ, ÎÉμ ¢ ¸²ÊÎ ¥ ¶·μ¤μ²Ó´μ° ¶μ²Ö·¨§ ͨ¨ ´Ê±²μ´ ¢ ¸¥Î¥´¨¥ ¢Ìμ¤ÖÉ ¤¢¥ ´¥§ ¢¨¸¨³Ò¥ ¶μ²Ö·¨§ Í¨μ´´Ò¥ ¸É·Ê±ÉÊ·´Ò¥ ËÊ´±Í¨¨ g1 ¨ g6 ¢ μɲ¨Î¨¥ μÉ Ô²¥±É·μ³ £´¨É´ÒÌ
¶·μÍ¥¸¸μ¢ £²Ê¡μ±μ´¥Ê¶·Ê£μ£μ · ¸¸¥Ö´¨Ö, £¤¥ Éμ²Ó±μ μ¤´ ¸É·Ê±ÉÊ·´ Ö ËÊ´±Í¨Ö g1γ .
158 ’¨³μϨ´ …. ‘., ’¨³μϨ´ ‘. ˆ.
2. ˆ‡‚‹…—…ˆ… ‹Ÿˆ‡–ˆ›• ‘’“Š’“›• ”“Š–ˆ‰
ˆ‡ ‘ˆŒŒ…’ˆ‰
ˆ´Ëμ·³ Í¨Ö μ ¸É·Ê±ÉÊ·¥ ´Ê±²μ´ , ¢ Éμ³ Î¨¸²¥ ¸¶¨´μ¢μ°, ¸μ¤¥·¦¨É¸Ö ¢ ¸É·Ê±ÉÊ·´ÒÌ ËÊ´±Í¨ÖÌ F1,2,3 ¨ g1,6 . ‚¸²¥¤¸É¢¨¥ ÔÉμ£μ μ´¨ ¶·¥¤¸É ¢²ÖÕÉ ¶·¥¤³¥É ¨¸¸²¥¤μ¢ ´¨Ö
¢ ¶·μÍ¥¸¸ Ì £²Ê¡μ±μ´¥Ê¶·Ê£μ£μ ²¥¶Éμ´-´Ê±²μ´´μ£μ · ¸¸¥Ö´¨Ö. μÔÉμ³Ê ¢ ¦´μ° § ¤ Î¥° Ö¢²Ö¥É¸Ö ¶μ²ÊÎ¥´¨¥ ¸É·Ê±ÉÊ·´ÒÌ ËÊ´±Í¨° ¨§ ¨§³¥·Ö¥³ÒÌ ¢¥²¨Î¨´. ‚ ¶·μÍ¥¸¸ Ì ¸
´¥¶μ²Ö·¨§μ¢ ´´Ò³¨ ¶Êα ³¨ ¨ ³¨Ï¥´Ö³¨ ¸É·Ê±ÉÊ·´Ò¥ ËÊ´±Í¨¨ F2 (¨²¨ F1 ) ¨ F3 ¶μ²ÊÎ ÕÉ ´¥¶μ¸·¥¤¸É¢¥´´μ ¨§ ¸¥Î¥´¨° · ¸¸¥Ö´¨Ö (¸³. (5)). ˆ´ Ö ¸¨ÉÊ Í¨Ö ¨³¥¥É ³¥¸Éμ
¢ ¸²ÊÎ ¥ ¶μ²Ö·¨§ ͨ¨ ´ Î ²Ó´ÒÌ Î ¸É¨Í ¢ £²Ê¡μ±μ´¥Ê¶·Ê£μ³ ²¥¶Éμ´-´Ê±²μ´´μ³ · ¸¸¥Ö´¨¨. — ¸ÉÓ ¸¥Î¥´¨Ö · ¸¸¥Ö´¨Ö, μ¡Ê¸²μ¢²¥´´ Ö ¶μ²Ö·¨§ ͨ¥° Î ¸É¨Í (¤²Ö ´¥°É·¨´´ÒÌ
¶·μÍ¥¸¸μ¢ ¸³. (6)), Ö¢²Ö¥É¸Ö ¸· ¢´¨É¥²Ó´μ ³ ²μ° ¨ ¢¸²¥¤¸É¢¨¥ ÔÉμ£μ ɷʤ´μ ¨§³¥·¨³μ°
Ô±¸¶¥·¨³¥´É ²Ó´μ. μÔÉμ³Ê ¢ ¶μ²Ö·¨§ Í¨μ´´ÒÌ Ô±¸¶¥·¨³¥´É Ì ¨§³¥·ÖÕÉ μÉ´μ¸¨É¥²Ó´Ò¥
¢¥²¨Î¨´Ò Å ¸¨³³¥É·¨¨, ¶·¥¤¸É ¢²ÖÕШ¥ ¸μ¡μ° (¢ ¸²ÊÎ ¥ ¶·μ¤μ²Ó´μ° ¶μ²Ö·¨§ ͨ¨) μÉ´μÏ¥´¨¥ · §´μ¸É¨ ¸¥Î¥´¨° ¸ ¶ · ²²¥²Ó´Ò³ ¨ ´É¨¶ · ²²¥²Ó´Ò³ ´ ¶· ¢²¥´¨Ö³¨ ¸¶¨´μ¢
²¥¶Éμ´ ¨ ´Ê±²μ´ ± ¸Ê³³¥ ÔÉ¨Ì ¸¥Î¥´¨°. ’¥³ ¸ ³Ò³ ¢ Ψ¸²¨É¥²¥ ¢Ò¤¥²Ö¥É¸Ö ¢ ®Î¨¸Éμ³¯
d2 σ p , ¢ §´ ³¥´ É¥²¥ Å ´¥¶μ²Ö·¨§ Í¨μ´´ Ö
¢¨¤¥ ¶μ²Ö·¨§ Í¨μ´´ Ö Î ¸ÉÓ ¸¥Î¥´¨Ö
dx dy
d2 σ a Î ¸ÉÓ
, É. ¥. ¸¨³³¥É·¨Ö ¥¸ÉÓ A = d2 σ p d2 σ a ¨ ¢Ò· ¦ ¥É¸Ö Î¥·¥§ ¸É·Ê±ÉÊ·´Ò¥
dx dy
ËÊ´±Í¨¨ (¸³. (5), (6)). ‘²¥¤μ¢ É¥²Ó´μ, ¶μ²Ö·¨§ Í¨μ´´Ò¥ ¸É·Ê±ÉÊ·´Ò¥ ËÊ´±Í¨¨ ¤μ²¦´Ò
¨§¢²¥± ÉÓ¸Ö ¨§ ¸¨³³¥É·¨° ¸ ¨¸¶μ²Ó§μ¢ ´¨¥³ ¨§¢¥¸É´ÒÌ ¶ · ³¥É·¨§ ͨ° ʸ·¥¤´¥´´ÒÌ ¶μ
¸¶¨´Ê ¸É·Ê±ÉÊ·´ÒÌ ËÊ´±Í¨° F1,2,3 .
‚ Ô²¥±É·μ³ £´¨É´ÒÌ ¶·μÍ¥¸¸ Ì £²Ê¡μ±μ´¥Ê¶·Ê£μ£μ ²¥¶Éμ´-´Ê±²μ´´μ£μ · ¸¸¥Ö´¨Ö É ± Ö § ¤ Î ·¥Ï ¥É¸Ö ¤μ¸É ÉμÎ´μ ¶·μ¸Éμ ¢ ¸²ÊÎ ¥ ¶·μ¤μ²Ó´μ° ¶μ²Ö·¨§ ͨ¨ ´Ê±²μ´ , ¶μ¸±μ²Ó±Ê ¢±² ¤Ò ¢¨·ÉÊ ²Ó´μ° ¸¨³³¥É·¨¨ A2 ¨ ¸É·Ê±ÉÊ·´μ° ËÊ´±Í¨¨ g2 ¶·¥´¥¡·¥¦¨³μ
³ ²Ò ¨ ¨§ ¨§³¥·Ö¥³μ° ¸¨³³¥É·¨¨ A ³μ¦´μ ¶·Ö³μ ¶μ²ÊΨÉÓ ¸É·Ê±ÉÊ·´ÊÕ
ËÊ´±Í¨Õ g1 [1, 3].
μ²Ö·¨§ Í¨μ´´Ò¥ ¸¨³³¥É·¨¨ ¤²Ö ¶·μÍ¥¸¸μ¢ (1) μ¶·¥¤¥²¨³ ± ± ¸²¥¤ÊÕÐÊÕ ±μ³¡¨´ Í¨Õ ¸¥Î¥´¨° (7):
↓↑,↑↑
↓↓,↑↓
d2 σν,ν̄
− d2 σν,ν̄
.
(8)
Aν,ν̄ =
↓↑,↑↑
↓↓,↑↓
d2 σν,ν̄
+ d2 σν,ν̄
¥·¢ Ö ¸É·¥²± ¢ (8) ¸μμÉ¢¥É¸É¢Ê¥É ¸¶¨· ²Ó´μ¸É¨ ´¥°É·¨´μ ↓ ¨²¨ ´É¨´¥°É·¨´μ ↑, ¢Éμ· Ö Å ´ ¶· ¢²¥´¨Õ ¸¶¨´ ´Ê±²μ´ ↑ (PN = 1) ¨ ↓ (PN = −1). ‘ ¶μ³μÐÓÕ (7) ¤²Ö
¸¨³³¥É·¨° ¶μ²ÊÎ ¥³ ¢Ò· ¦¥´¨Ö Î¥·¥§ ¸É·Ê±ÉÊ·´Ò¥ ËÊ´±Í¨¨:
Aν,ν̄ (x, Q2 ) =
y1+ g6ν,ν̄ (x, Q2 ) ± y1− g1ν,ν̄ (x, Q2 )
.
y−
y1+ F1ν,ν̄ (x, Q2 ) ± 1 F3ν,ν̄ (x, Q2 )
2
(9)
‚ μɲ¨Î¨¥ μÉ Ô²¥±É·μ³ £´¨É´ÒÌ ¶·μÍ¥¸¸μ¢ £²Ê¡μ±μ´¥Ê¶·Ê£μ£μ · ¸¸¥Ö´¨Ö ¨§¢²¥Î¥´¨¥
¶μ²Ö·¨§ Í¨μ´´ÒÌ ¸É·Ê±ÉÊ·´ÒÌ ËÊ´±Í¨° ¢ £²Ê¡μ±μ´¥Ê¶·Ê£μ³ · ¸¸¥Ö´¨¨ ¸ § ·Ö¦¥´´Ò³
¸² ¡Ò³ Éμ±μ³ Ö¢²Ö¥É¸Ö ´¥É·¨¢¨ ²Ó´μ° § ¤ Î¥°, ¶μ¸±μ²Ó±Ê ¸¨³³¥É·¨¨ (9) ¸μ¤¥·¦ É ¤¢¥
´¥§ ¢¨¸¨³Ò¥ ¸É·Ê±ÉÊ·´Ò¥ ËÊ´±Í¨¨ g1 ¨ g6 .
Î¥¢¨¤´μ, ÎÉμ ¤²Ö ¨§¢²¥Î¥´¨Ö g1,6 ¨§ (9) ´¥μ¡Ì줨³μ ¤μ¶μ²´¨É¥²Ó´μ¥ ¸μμÉ´μÏ¥´¨¥,
¸¢Ö§Ò¢ ÕÐ¥¥ Ôɨ ËÊ´±Í¨¨. ‚ · ¡μÉ¥ [14] g1 ¨ g6 μ¶·¥¤¥²Ö²¨¸Ó ¸ ¶μ³μÐÓÕ ´ ¡μ· ¨§³¥-
ˆ§¢²¥Î¥´¨¥ ¶μ²Ö·¨§ Í¨μ´´ÒÌ ¸É·Ê±ÉÊ·´ÒÌ ËÊ´±Í¨° ¨§ ¸¨³³¥É·¨° 159
·Ö¥³ÒÌ ¢¥²¨Î¨´, ¢±²ÕÎ ÕÐ¥£μ ¢¨·ÉÊ ²Ó´ÊÕ ËμÉμ´-´Ê±²μ´´ÊÕ ¸¨³³¥É·¨Õ A1 £²Ê¡μ±μ´¥Ê¶·Ê£μ£μ ²¥¶Éμ´-´Ê±²μ´´μ£μ · ¸¸¥Ö´¨Ö, É. ¥. ¨¸¶μ²Ó§μ¢ ²¨¸Ó ´ ¡²Õ¤ ¥³Ò¥ ¸¨³³¥É·¨¨
¤¢ÊÌ É¨¶μ¢ ¶·μÍ¥¸¸μ¢ £²Ê¡μ±μ´¥Ê¶·Ê£μ£μ · ¸¸¥Ö´¨Ö: ( ´É¨)´¥°É·¨´μ ´ ´Ê±²μ´ Ì (μ¡³¥´
W -¡μ§μ´μ³) ¨ § ·Ö¦¥´´ÒÌ ²¥¶Éμ´μ¢ ´ ´Ê±²μ´ Ì (γ-μ¡³¥´).
Š·μ³¥ Éμ£μ, ¶·¥¤²μ¦¥´´ Ö É ³ ¸Ì¥³ ¨¸¶μ²Ó§Ê¥É¸Ö Éμ²Ó±μ ¤²Ö ¤¥°É·μ´´μ° ³¨Ï¥´¨ ¨,
¸²¥¤μ¢ É¥²Ó´μ, ´μ¸¨É μ£· ´¨Î¥´´Ò° Ì · ±É¥·. ‡¤¥¸Ó ¶·¥¤² £ ¥É¸Ö ´μ¢Ò° ¸¶μ¸μ¡ ¨§¢²¥Î¥´¨Ö ¸É·Ê±ÉÊ·´ÒÌ ËÊ´±Í¨° g1 ¨ g6 ¨§ ¸¨³³¥É·¨°, ¨§³¥·Ö¥³ÒÌ Éμ²Ó±μ ¢ Ô±¸¶¥·¨³¥´É Ì ¸
ÊÎ ¸É¨¥³ ´¥°É·¨´μ, ¶·¨³¥´¨³Ò° ¤²Ö ²Õ¡μ° ³¨Ï¥´¨.
„²Ö ÔÉμ£μ · ¸¸³μÉ·¨³ ¶·μÍ¥¸¸Ò £²Ê¡μ±μ´¥Ê¶·Ê£μ£μ · ¸¸¥Ö´¨Ö ¶μ²Ö·¨§μ¢ ´´ÒÌ § ·Ö¦¥´´ÒÌ ²¥¶Éμ´μ¢, Ö¢²ÖÕШ¥¸Ö μ¡· É´Ò³¨ ¶μ μÉ´μÏ¥´¨Õ ± ´¥°É·¨´´Ò³ ·¥ ±Í¨Ö³ (1):
l− (l+ ) + N → ν(ν̄) + X,
(10)
£¤¥ l = e, μ.
‚ ²¨¤¨·ÊÕÐ¥³ ¶μ·Ö¤±¥ Š•„ ¤²Ö ¸É·Ê±ÉÊ·´ÒÌ ËÊ´±Í¨° ¶·μÍ¥¸¸μ¢ (1) ¨ (10) ¨³¥ÕÉ
³¥¸Éμ ¸²¥¤ÊÕШ¥ ¸μμÉ¢¥É¸É¢¨Ö:
−
ν̄
l
g1,6
(x, Q2 ) = g1,6
(x, Q2 ),
−
ν̄
l
F1,3
(x, Q2 ) = F1,3
(x, Q2 ),
+
ν
l
g1,6
(x, Q2 ) = g1,6
(x, Q2 ),
+
ν
l
F1,3
(x, Q2 ) = F1,3
(x, Q2 ).
(11)
¡²Õ¤ ¥³Ò¥ ¸¨³³¥É·¨¨ Al− ,l+ (x, Q2 ) ¶·μÍ¥¸¸μ¢ (10) [18] § ¶¨Ï¥³ ¢ ¢¨¤¥
−
,l+
−
+
(x, Q2 ) ± y1− g1l ,l (x, Q2 )
.
Al− ,l+ (x, Q ) =
y1− l− ,l+
+ l− ,l+
2
2
F
y1 F1
(x, Q ) ±
(x, Q )
2 3
2
y1+ g6l
(12)
‘ ÊÎ¥Éμ³ ¸μμÉ´μÏ¥´¨° (11) ¸¨³³¥É·¨¨ Al− ,l+ (x, Q2 ) (12) ¶·¥¤¸É ¢¨³ Î¥·¥§ ¸É·Ê±ÉÊ·´Ò¥ ËÊ´±Í¨¨ g1ν,ν̄ (x, Q2 ) ¨ g6ν,ν̄ (x, Q2 ) É ±¨³ μ¡· §μ³:
Al− ,l+ (x, Q2 ) =
y1+ g6ν̄,ν (x, Q2 ) ± y1− g1ν̄,ν (x, Q2 )
.
y1− ν̄,ν
+ ν̄,ν
2
2
F (x, Q )
y1 F1 (x, Q ) ±
2 3
(13)
‘μμÉ´μÏ¥´¨Ö (9), (13) ¶μ§¢μ²ÖÕÉ ¢Ò¤¥²¨ÉÓ ¸É·Ê±ÉÊ·´Ò¥ ËÊ´±Í¨¨ g1ν,ν̄ (x, Q2 )
¨
¶μ¸±μ²Ó±Ê F1ν,ν̄ (x, Q2 ), F3ν,ν̄ (x, Q2 ) ¨§¢¥¸É´Ò ¨§ ´¥°É·¨´´ÒÌ Ô±¸¶¥·¨³¥´Éμ¢
´ ´¥¶μ²Ö·¨§μ¢ ´´ÒÌ ³¨Ï¥´ÖÌ. ‚ ·¥§Ê²ÓÉ É¥ ¶μ²ÊÎ ¥³
+
y
1
F ν,ν̄ (x, Q2 )
ν,ν̄
2
g1 (x, Q ) =
Aν,ν̄ (x, Q2 ) 1− F1ν,ν̄ (x, Q2 ) ± 3
∓
2
2
y1
+
ν,ν̄
2
y
(x,
Q
)
F
ν,ν̄
∓ Al+ ,l− (x, Q2 ) 1− F1 (x, Q2 ) ∓ 3
,
2
y1
(14)
1
y1− ν,ν̄
ν,ν̄
ν,ν̄
2
2
2
2
Aν,ν̄ (x, Q ) F1 (x, Q ) ± + F3 (x, Q ) +
g6 (x, Q ) =
2
2y1
−
y
ν,ν̄
ν,ν̄
+ Al+ ,l− (x, Q2 ) F1 (x, Q2 ) ∓ 1+ F3 (x, Q2 ) .
2y1
g6ν,ν̄ (x, Q2 ),
160 ’¨³μϨ´ …. ‘., ’¨³μϨ´ ‘. ˆ.
ɳ¥É¨³, ÎÉμ ¤²Ö ´ Ì즤¥´¨Ö ¸É·Ê±ÉÊ·´ÒÌ ËÊ´±Í¨° ¶μ Ëμ·³Ê² ³ (14) ¤μ¸É Éμδμ
¤ ´´ÒÌ Éμ²Ó±μ Ô±¸¶¥·¨³¥´Éμ¢ (1) ¨ (10) ¶μ £²Ê¡μ±μ´¥Ê¶·Ê£μ³Ê · ¸¸¥Ö´¨Õ ¸ § ·Ö¦¥´´Ò³
Éμ±μ³ ¸ ÊÎ ¸É¨¥³ ´¥°É·¨´μ. ÉμÉ ¸¶μ¸μ¡ ¶·¨³¥´¨³ ¤²Ö ²Õ¡μ° ³¨Ï¥´¨.
‚¥²¨Î¨´ y1+ = 0 ¶·¨ ²Õ¡μ³ §´ Î¥´¨¨ ¸±¥°²¨´£μ¢μ° ¶¥·¥³¥´´μ° y ¢ ¶·¥¤¥² Ì ¥¥
¨§³¥´¥´¨Ö ¢ μ¡² ¸É¨ £²Ê¡μ±μ´¥Ê¶·Ê£μ£μ · ¸¸¥Ö´¨Ö [16]
0 < y 1.
—Éμ ± ¸ ¥É¸Ö y1− , Éμ y1− = 0 ¶·¨ y = 0, ´μ ÔÉμ §´ Î¥´¨¥ ´¥ ¢Ìμ¤¨É ¢ ±¨´¥³ ɨΥ¸±ÊÕ
μ¡² ¸ÉÓ ¶¥·¥³¥´´μ° y.
l−
ɳ¥É¨³, ÎÉμ ¢ ¶·¥¤² £ ¥³μ³ ¶μ¤Ì줥 ³μ¦´μ μ¶·¥¤¥²¨ÉÓ ¸É·Ê±ÉÊ·´Ò¥ ËÊ´±Í¨¨ g1,6
l+
¨ g1,6
¶·μÍ¥¸¸μ¢ (10) ¸ ¶μ³μÐÓÕ ¸¨³³¥É·¨° Al− ,l+ (x, Q2 ) (12), Aν,ν̄ (x, Q2 ) (9) ¨ (11):
− +
+
− +
y
1
F l ,l (x, Q2 )
±Al− ,l+ (x, Q2 ) 1− F1l ,l (x, Q2 ) ± 3
=
∓
2
2
y1
+
y1 l− ,l+
l− ,l+
2
2
2
(x, Q ) ∓ F3
(x, Q ) , (15)
∓ Aν̄,ν (x, Q ) − F1
y1
− +
− +
1
y− − +
Al− ,l+ (x, Q2 ) F1l ,l (x, Q2 ) ± 1+ F3l ,l (x, Q2 ) +
g6l ,l (x, Q2 ) =
2
2y1
y1− l− ,l+
l− ,l+
2
2
2
+ Aν̄,ν (x, Q ) F1
(x, Q ) ∓ + F3
(x, Q ) .
2y1
− +
g1l ,l (x, Q2 )
‡Š‹—…ˆ…
‚ ´ ¸ÉμÖÐ¥° · ¡μÉ¥ ¶·¥¤²μ¦¥´ ¸¶μ¸μ¡ ¨§¢²¥Î¥´¨Ö ¶μ²Ö·¨§ Í¨μ´´ÒÌ ¸É·Ê±ÉÊ·´ÒÌ
ËÊ´±Í¨° g1 ¨ g6 ¢ ´¥°É·¨´´ÒÌ ¶·μÍ¥¸¸ Ì (1) ¨ ²¥¶Éμ´-´Ê±²μ´´μ³ · ¸¸¥Ö´¨¨ (10) ´¥¶μ¸·¥¤¸É¢¥´´μ ¨§ ¨§³¥·Ö¥³ÒÌ ¸¨³³¥É·¨° ÔÉ¨Ì ¶·μÍ¥¸¸μ¢.
„²Ö ´ Ì즤¥´¨Ö ¸É·Ê±ÉÊ·´ÒÌ ËÊ´±Í¨° ¶μ Ëμ·³Ê² ³ (14), (15) ¤μ¸É ÉμÎ´μ ¤ ´´ÒÌ
Éμ²Ó±μ Ô±¸¶¥·¨³¥´Éμ¢ ¶μ £²Ê¡μ±μ´¥Ê¶·Ê£μ³Ê · ¸¸¥Ö´¨Õ ¸ § ·Ö¦¥´´Ò³ ¸² ¡Ò³ Éμ±μ³ ¸
ÊÎ ¸É¨¥³ ´¥°É·¨´μ. „ ´´Ò° ¸¶μ¸μ¡ ¶·¨³¥´¨³ ¤²Ö ²Õ¡μ° ³¨Ï¥´¨, ¶μ§¢μ²Ö¥É ¶μ²ÊÎ ÉÓ
¸É·Ê±ÉÊ·´Ò¥ ËÊ´±Í¨¨ g1 ¨ g6 ¨§ ¸¨³³¥É·¨° ¢ μ¡² ¸É¨ £²Ê¡μ±μ´¥Ê¶·Ê£μ£μ · ¸¸¥Ö´¨Ö
0 < y 1.
‘ˆ‘Š ‹ˆ’…’“›
1. Kuhn S. E., Chen J.-P., Leader E. Spin Structure of the Nucleon-Status and Recent Results // Prog.
Nucl. Part. Phys. 2009. V. 63, No. 1. P. 1Ä69.
2. Burkardt M., Miller A., Nowak W.-D. Spin-Polarized High-Energy Scattering of Charged Leptons
on Nucleons // Rep. Prog. Phys. 2010. V. 73. P. 016201.
3. Aidala A. et al. The Spin Structure of the Nucleon. arxiv: 1209.2803 [hep-ph]. 43 p.
4. Forte S., Mangano M. L., Ridolˇ G. Polarized Parton Distribution from Charged-Current DeepInelastic Scattering and Future Neutrino Factories // Nucl. Phys. B. 2001. V. 602. P. 585Ä621.
ˆ§¢²¥Î¥´¨¥ ¶μ²Ö·¨§ Í¨μ´´ÒÌ ¸É·Ê±ÉÊ·´ÒÌ ËÊ´±Í¨° ¨§ ¸¨³³¥É·¨° 161
5. Newman P. Deep Inelastic Scattering at the TeV Energy Scale and the LHeC Project // Nucl. Phys.
Proc. Suppl. 2009. V. 191. P. 307Ä319.
6. Accardi A. et al. Nuclear Physics with a Medium-Energy ElectronÄIon Collider // Eur. Phys. J. A.
2012. V. 48. P. 92.
7. Guzey V. The ElectronÄIon Collider // AIP Conf. Proc. 2009. V. 1182. P. 803Ä806.
8. Aschenauer E. C., Stratmann M., Sassoth R. Helicity Parton Distributions at a Future ElectronÄIon
Collider: A Quantitative Appraisal // Phys. Rev. D. 2012. V. 86. P. 054020.
9. ˜¨²ÓÍ¥¢ ‚. „. Šμ²² °¤¥·Ò Î ¸É¨Í ¢Ò¸μ±¨Ì Ô´¥·£¨°: ¶·μÏ¥¤Ï¨¥ 20 ²¥É, ¶·¥¤¸ÉμÖШ¥ 20 ²¥É
¨ μɤ ²¥´´μ¥ ¡Ê¤ÊÐ¥¥ // “”. 2012. ’. 182, º 10. ‘. 1033Ä1046.
10. Abelleira Fernandez J. L. A Large Hadron Electron Collider at CERN. arxiv: 1211.4831 [hep-ex].
18 p.
11. Kaplan D. M. Muon Collider / Neutrino Factory: Status and Prospects // Nucl. Instr. Meth. A. 2000.
V. 453. P. 37Ä48.
12. Alsharo'a Mohammad M. et al. Recent Progress in Neutrino Factory and Muon Collider Research
within the Muon Collaboration // Phys. Rev. ST Accel. Beams. 2003. V. 6. P. 081001.
13. Ravishankar V. Charged Current Deep Inelastic Scattering on Polarized Nucleon and Nuclear
Targets // Nucl. Phys. B. 1992. V. 374, No. 2. P. 309Ä326.
14. ’¨³μϨ´ ‘. ˆ. ƒ²Ê¡μ±μ´¥Ê¶·Ê£μ¥ · ¸¸¥Ö´¨¥ ¸ § ·Ö¦¥´´Ò³ Éμ±μ³ ¨ ¸¶¨´ ¶·μÉμ´ // Ÿ”. 1998.
’. 61, º 1. ‘. 119Ä124.
15. ’¨³μϨ´ ‘. ˆ. ˆ¸¸²¥¤μ¢ ´¨¥ ¸¶¨´ ´Ê±²μ´ ¢ ´¥°É·¨´´ÒÌ ¶·μÍ¥¸¸ Ì // Ÿ”. 2003. ’. 66, º 2.
‘. 327Ä331.
16. ¨²¥´Ó±¨° ‘. Œ. ‚¢¥¤¥´¨¥ ¢ ¤¨ £· ³³Ò ”¥°´³ ´ ¨ ˨§¨±Ê Ô²¥±É·μ¸² ¡μ£μ ¢§ ¨³μ¤¥°¸É¢¨Ö.
Œ.: ´¥·£μ É쳨§¤ É, 1990. 326 ¸.
17. Kaur J. Spin Distribution in the QuarkÄParton Model // Nucl. Phys. B. 1977. V. 128. P. 219Ä251.
18. Œ ±¸¨³¥´±μ . ‚., ’¨³μϨ´ …. ‘. ƒ²Ê¡μ±μ´¥Ê¶·Ê£μ¥ lp-· ¸¸¥Ö´¨¥ ¸ § ·Ö¦¥´´Ò³ Éμ±μ³ ¨ ¸¶¨´
¶·μÉμ´ // ˆ§¢. ¥² ·Ê¸¨. ‘¥·. ˨§.-³ É. ´ ʱ. 2008. º 2. ‘. 73Ä77.
μ²ÊÎ¥´μ 30 ³ Ö 2013 £.
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